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$xhtml = array(
	'<{title}>' => 'Throwing away money',
	'takedown' => '2017-11-01',
	'<{body}>' => <<<END
<img src="/img/CC_BY-SA_4.0/y.st./weblog/2019/03/25.jpg" alt="Flowering saplings" class="framed-centred-image" width="649" height="480"/>
<section id="drudgery">
	<h2>Drudgery</h2>
	<p>
		I asked the proctor to schedule my exams, plural, for this Thursday if possible.
		Instead, they asked which exam I meant, singular, and scheduled the longer one in the mean time while they waited for an answer, saying they could correct it if that didn&apos;t work.
		We got the matter cleared up though, so both exams are now scheduled.
		I begin at 13:30.
	</p>
	<p>
		My discussion posts for the day:
	</p>
	<blockquote>
		<p>
			The result of hierarchical clustering is a dendrogram, which is a tree structure explaining the similarities found in the data.
			Unlike in K-means clustering, we do not need to know beforehand how many clusters the data need be organised into.
			This can be very helpful in many cases.
			Sometimes, we know the number of clusters needed based on the problem, but other times, not so much.
			The usual way to build a dendogram is to start at the leaf nodes, which represent the data points, and start merging those leaves into branches, working from the bottom up and combining like items.
			As we work our way up, branches and leaves combine further, allowing more and more difference between the leaves in the subtree.
		</p>
		<p>
			It reminds me very much of taxonomy.
			We humans, for example, are a species of apes.
			If you look at our ear shape, our hands, our general body shape, et cetera, you see we fit in rather well when grouped with other apes, such as gorillas and chimpanzees.
			Further up our tree, we have other mammals.
			Like any mammal, humans have hair and mammary glands.
			However, try comparing us to house cats, which are also mammals.
			They have hair and mammary glands like us, but their body shape is different, they have tails, their ears are pointy and on the top of their heads, and their paws are terrible at grabbing things, unlike our own.
			We look much more similar to our fellow apes than we do felines, and our branch combines with the feline branch further up the evolutionary tree than where it combines with the rest of the apes.
		</p>
		<p>
			Generating the dendrogram is done via mathematics and does not need much decision-making.
			Once you have the dendrogram, that is when you can begin your clustering.
			Clustering is done by cutting off the dendrogram at a given point.
			Change the cut to tune the results, so an algorithm doing this should know how about how many clusters to aim for or what minimum/maximum cluster size to accept.
			If you make the cut higher up, you will get fewer, more diverse clusters.
			In the taxonomy example, you might get a cluster representing all mammals if you make a mid-level cut, or a cluster representing all animals if you cut the evolutionary tree even higher up, separating us only from other kingdoms such as plants and fungi.
			We end up grouped with things very different from ourselves, such as sponges and sea jellies.
			If you cut the dendrogram very low, you end up with clusters of very similar things, but you end up with many more clusters.
			In the taxonomy example, you would end up with an ape cluster, in which everything has our basic body shape, but there are not many species in this cluster.
		</p>
		<div class="APA_references">
			<h3>References:</h3>
			<p>
				James, G., Witten, D., Hastie, T., &amp; Tibshirani, R. (2013). <a href="https://www-bcf.usc.edu/~gareth/ISL/ISLR%20First%20Printing.pdf">An Introduction to Statistical Learning with Applications in R</a>. Retrieved from <code>https://www-bcf.usc.edu/~gareth/ISL/ISLR%20First%20Printing.pdf</code>
			</p>
		</div>
	</blockquote>
	<blockquote>
		<p>
			My understanding is that species were originally classified without using genetic tools, based solely on what we can see of them outside their cells.
			This process is still used, but with genetics added on in cases we can actually get a genetic sample.
			(For example, some  extinct species are classified using only data from the fossil record because that&apos;s all we have on them.)
			The amazing thing though is that genetic testing backs up what we already knew before genetic testing was invented.
			The evolutionary tree is pretty much just what we expect it to be.
			Having genetics as an extra form of evidence is awesome though.
		</p>
		<p>
			I wish you luck on the final as well!
			I home we&apos;re not tested heavily on those equations we read but didn&apos;t put into practice.
			I couldn&apos;t figure out how to use most of them.
		</p>
	</blockquote>
</section>
<section id="credit">
	<h2>Credit card</h2>
	<p>
		The credit card company that won&apos;t let me activate the card they sent me sent me another credit card offer today.
		It&apos;s the same offer I already accepted.
		I guess they&apos;re now pretending they didn&apos;t send me a card at all and that I never accepted their offer.
		This is so stupid.
		I guess I&apos;m just going to ignore them.
	</p>
</section>
<section id="pennies">
	<h2>Pennies in the trash</h2>
	<p>
		Tonight at work, a workmate took the trash bag out of the can beneath my register, and I noticed a bunch of pennies at the bottom.
		That was strange.
		Someone had thrown away a handful of coins!
		I asked them to leave the bag there, and I&apos;d deal with it so as to collect the pennies instead of putting them in the dumpster with the rest of the garbage.
		I thought it&apos;d be a simple matter of gathering the pennies to the same spot, then puncturing the bag there, but it turned out to be more complicated than that.
		In any case, I&apos;m not sure if I managed to save every last penny, but I did get nearly a dollar, which I dumped into my tip jar so I could deal with putting them away later.
		My workmates and I all agreed that it was odd that someone had thrown away that many coins, but there was no way to know who&apos;d done it or why.
	</p>
	<p>
		That is, until the head manager noticed all the pennies in my tip jar.
		They commented that I had quite a collection, so I explained where they&apos;d come from.
		It turns out <strong>*the head manager*</strong> was the one that threw them away!
		They&apos;d been in the register, but the head manager threw them away because they didn&apos;t want to bother counting them.
		What kind of logic is that!?
		First of all, they could have just left them in the register uncounted.
		Were they hurting anyone?
		Secondly, my tip jar was right there.
		They could have tossed them into it.
		It&apos;d&apos;ve been just as much effort as throwing them away.
		Third, they could have pocketed them, and deposited them at the bank, making the bank count them.
		The bank probably has a coin counter even, so it&apos;d&apos;ve been almost no effort for them.
		Both my credit unions have coin counters anyway; I don&apos;t see why many banks or credit unions <strong>*wouldn&apos;t*</strong> have a counter.
		The main disadvantage of this option though is that it&apos;d be theft.
		Very, very petty theft, but it&apos;d look bad.
		But the fourth option would have been the best of all.
		They could have dumped the pennies on the counter and I&apos;d&apos;ve rolled them.
		They wouldn&apos;t&apos;ve even needed to count half of them.
	</p>
	<p>
		For as long as I can remember, the head manager has been dumping piles of like coins on the counter near the registers.
		I didn&apos;t know what was up with the coins for the longest time, so I ignored them.
		They weren&apos;t my problem.
		But then once, the head manager told me to roll them.
		So I did.
		The next time they did it, I thought they were trying to signal me to roll them.
		But no, they weren&apos;t.
		They were grateful to have them rolled, but they were planning to do that themself later.
		So that solved the mystery.
		When they plan to roll the coins later, they dump them on the counter, probably to remind themself to go back and do that.
		They don&apos;t count them first either, they do that when rolling them, so there&apos;s always leftovers.
		Since then though, I&apos;ve always rolled the coins whenever I see them piled.
		At first, I did it to help the head manager.
		But I still do it even though I&apos;m fed up with the head manager.
		When the head manager ticked me off, I decided to stop, but went back and did rolled them anyway.
		The thing is, I feel really weird about not getting anything done, and there&apos;s always a slow period in which I struggle to find anything meaningful to accomplish.
		Rolling coins can always be done during those periods, or sometimes they can be rolled while indecisive customers are deciding what they want.
		Either way, the coins always get rolled before the head manager can get back to them if they leave them near the register I&apos;m working.
		Throwing them away made no sense.
	</p>
	<p>
		Whatever though.
		I used a slow period to get them out of the trash.
		There was nothing productive to do, so I didn&apos;t waste company time.
		I had something to do, and I got nearly a dollar for doing it.
		It&apos;s not much, but as I said yesterday, every penny counts.
	</p>
</section>
<section id="dealership">
	<h2>Dealership</h2>
	<p>
		As expected, the salesperson from the dealership didn&apos;t contact me about the $a[DMV] issues as they said they would.
	</p>
</section>
END
);
